[Haskell-cafe] Current state of dependent types in Haskell

Can anyone kindly point me at blog posts and/or articles on the subject? I would like to brush off my Haskell skills in that area with whatever new things that are hot. I once implemented type-level arithmetic in Haskell for sizing various hardware things but it is ages ago now. I would like to experiment with current state of affairs with type-level arithmetic and possibly experiment with adding structured values into the constraints.